[Rails] Delete the migration file

Reference target person

--Those who want to know how to operate the migration file

environment

$ rails -v
Rails 6.0.3.1

$ ruby -v
ruby 2.7.0p0 (2019-12-25 revision 647ee6f091) [x86_64-darwin19]

$ mysql --version
mysql  Ver 14.14 Distrib 5.7.29, for osx10.15 (x86_64) using  EditLine wrapper

Delete the migration file

Suppose you want to delete the file Add column to users

--Check the migration ID of the file you want to delete

$ rails db:migrate:status

 Status   Migration ID    Migration Name
--------------------------------------------------
   up     20200618162841  Create tweetposts
   up     20200620004226  Change tweetposts to tweets
  down    20200621075518  Create posts
  down    20200623102444  Change posts to chats
  down    20200627042358  Create users
   up     20200627080839  Create users
   up     20200627083356  Add column to users
  down    20200627220915  Change datatype content of chats
  down    20200710035709  Add user id to tweets

--Specify ID and bring down

$ rails db:migrate:down VERSION=Add column to users

--Move the downed file to the trash

$ rm db/migrate/20200703201452_add_column_to_users.rb

When the migration file is deleted before going down

********** no file **********I want to delete the file in the up state with the file

--Check the migration ID of the file you want to delete

$ rails db:migrate:status

 Status   Migration ID    Migration Name
--------------------------------------------------
   up     20200618162841  Create tweetposts
   up     20200620004226  Change tweetposts to tweets
  down    20200621075518  Create posts
  down    20200623102444  Change posts to chats
  down    20200627042358  Create users
   up     20200627080839  Create users
   up     20200627083356  Add column to users
  down    20200627220915  Change datatype content of chats
   up     20200703201452  ********** NO FILE **********
  down    20200710035709  Add user id to tweets

--Create a file with the same name as the deleted migration file name

$ touch db/migrate/20200703201452_add_column_to_users.rb

20200703201452_add_column_to_users.rb

class AddColumnToUsers < ActiveRecord::Migration
  def change
  end
end

• Down and delete the created migration file

$ rails db:migrate:down VERSION=20200703201452

$ rm db/migrate/20200703201452_add_column_to_users.rb